Rack::Spec

JSON Schema based Rack middlewares.

Usage

str = File.read("schema.json")
schema = JSON.parse(str)

use Rack::Spec::ErrorHandler
use Rack::Spec::RequestValidation, schema: schema
use Rack::Spec::ResponseValidation, schema: schema if ENV["RACK_ENV"] == "test"
use Rack::Spec::Mock, schema: schema if ENV["RACK_ENV"] == "mock"

Rack::Spec::RequestValidation

Validates request and raises errors below.

• Rack::Spec::RequestValidation::InvalidContentType
• Rack::Spec::RequestValidation::InvalidJson
• Rack::Spec::RequestValidation::InvalidParameter
• Rack::Spec::RequestValidation::LinkNotFound

$ curl http://localhost:9292/users
{
  "id": "link_not_found",
  "message": "Not found"
}

$ curl http://localhost:9292/apps -H "Content-Type: application/json" -d "invalid-json"
{
  "id": "invalid_json",
  "message": "Request body wasn't valid JSON"
}

$ curl http://localhost:9292/apps -H "Content-Type: text/plain" -d "{}"
{
  "id": "invalid_content_type",
  "message": "Invalid content type"
}

$ curl http://localhost:9292/apps -H "Content-Type: application/json" -d '{"name":"x"}'
{
  "id": "invalid_parameter",
  "message": "Invalid request.\n#/name: failed schema #/definitions/app/links/0/schema/properties/name: Expected string to match pattern \"/^[a-z][a-z0-9-]{3,50}$/\", value was: x."
}

Rack::Spec::ResponseValidation

Validates request and raises errors below.

• Rack::Spec::RequestValidation::InvalidResponseContentType
• Rack::Spec::RequestValidation::InvalidResponseType

$ curl http://localhost:9292/apps
{
  "id": "invalid_response_content_type",
  "message": "Response Content-Type wasn't for JSON"
}

$ curl http://localhost:9292/apps
{
  "id": "invalid_response_type",
  "message": "#: failed schema #/definitions/app: Expected data to be of type \"object\"; value was: [\"message\", \"dummy\"]."
}

Rack::Spec::Mock

Generates dummy response by using example property in JSON schema.

$ curl http://localhost:9292/apps/1
[
  {
    "id": "01234567-89ab-cdef-0123-456789abcdef",
    "name": "example"
  }
]

$ curl http://localhost:9292/apps/01234567-89ab-cdef-0123-456789abcdef
{
  "id": "01234567-89ab-cdef-0123-456789abcdef",
  "name": "example"
}

$ curl http://localhost:9292/apps/1 -d '{"name":"example"}'
{
  "id": "01234567-89ab-cdef-0123-456789abcdef",
  "name": "example"
}

$ curl http://localhost:9292/recipes
{
  "id": "example_not_found",
  "message": "No example found for #/definitions/recipe/id"
}

Rack::Spec::ErrorHandler

Returns appropriate error response including following properties when RequestValidation raises error.

• message: Human readable message
• id: Error type identifier listed below
  • invalid_content_type
  • invalid_json
  • invalid_parameter
  • invalid_response_content_type
  • invalid_response_type
  • link_not_found

Here is a tree of all possible errors defined in Rack::Spec.

StandardError
|
Rack::Spec::Error
|
|--Rack::Spec::Mock::Error
|  |
|  `--Rack::Spec::RequestValidation::ExampleNotFound
|
|--Rack::Spec::RequestValidation::Error
|  |
|  |--Rack::Spec::RequestValidation::InvalidContentType
|  |
|  |--Rack::Spec::RequestValidation::InvalidJson
|  |
|  |--Rack::Spec::RequestValidation::InvalidParameter
|  |
|  `--Rack::Spec::RequestValidation::LinkNotFound
|
`--Rack::Spec::ResponseValidation::Error
   |
   |--Rack::Spec::ResponseValidation::InvalidResponseContentType
   |
   `--Rack::Spec::ResponseValidation::InvalidResponseType